Transcript
£i commodore
Commodore
Canada's
Tech/News
Periodical
The Transactor Bits
&
*2
Pieces
Disabling The
Here If you
Issue
are
STOP Key
a
couple
don't need the
of
ways
internal
Disable with Restore with
If you do need the little Basic routine that
110 120
D$
=
disable
POKE 144, POKE 144,
Notice that to disable you address of the IRQ vector, Commodore Basic.
100
to
the
4.0
STOP
key.
clock: 88 85
simply add three to low order as with all other versions of
clock, Jim does it:
Eutterfielc
has
a
tidy
screen
4032
"20>:??:9??8=9;004<58>4"
FOR J = 1 TO LEN (D$)/2 POKE J+852, ASC(HID$(D$,J*2-l))*16
+ ASC(MID$(D$,J*2))-816
WordPro
given
and
13 0
NEXT
The
40-8032
WordPro 3 Plus will work these POKE conversions: 1. 2.
5. 6.
LOAD POKE POKE POKE POKE POKE
2438, 2439,
108 252
7.
POKE 2440,
255
3. 4.
"WORDPRO 60 84, 36
While on the subject a SEOuential file
you
get
but is!
if
For
now
the
First
method
type
we'll
on
seems
about put
one
5
60 88,
24
6090,
147
the
new
12"
3+
of WordPro, several have asked "Can into WordPro?". The answer is yes,
a
little
dozen on
each
abnormal,
variable line.
that's
blocks Now
(Control
using
Duplicate" function, fill the whole vorlspace blocks and Memorize this for future use. The
because
with
the
it
P) .
"Line
variable
Index
Transactor
32
Pits L Pieces Disabling STOP WordPro & The 40-8032 CBI! ROMs C?l':
8010
Notes
1 1 1 3 4
PET Show Report
6
4C/80 Video Interface Dial-A-ROMs Joystick/Keyboard Routine That Hardware Do I Have?
11 29 30 34
The Tat A First
37
40 Look
At The
SUPERPET
40
Pick some SEQ file that you would like to edit using WordPro. The idea here is to make WordPro "think" that you1 re going to use the SEQ file data to insert into a form letter which, in this case, is just blank. The printer must be
connected.
Type:
Control
'O'utput +
'S'
WordPro will prompt you for the name of the SEQ file. Type it in and hit return. The variable blocks will begin to fill up with the data from the SEQ file. However, if the last variable block is filled with data, WordPro will procede to Output to the printer* Hitting STOP halts output but then WordPro goes and erases the contents of you*re variable blocks... ARGHH! Solution?.. Always have at least one more variable block in WordPro text than you have carriage returns in you1re SEQ file. This way WordPro won't be able to find enough data to fill all the blocks and reports an error, at which point you're data is left in tact. You may have to keep adding variable blocks to the point, where the SEQ file is exhausted before the last block. This may require more than one block on a line. However, a sequential output to disk will concatenate blocks on the same line which may not be too desirable. To delimit blocks with carriage returns, you must either keep each item on its own line or use the programmable character facility in WordPro. Define some character, say 1, equal to ASCII 13 ('tick'lslS) and insert Control:1s between the blocks. See WordPro nanual for more on defining special characters.
Commodore
ROMs
Retrofit ROM sets are available upgrade to BASIC 4.0 and/or DOS 2.0. (suggested retail) $100.00.
-
3
-
from Cost
your dealer for for each set is
CDf!
901Q
Notes
Paul
The manual that is supplied fairly good, but I found I still lines to really get it right.
My
objective was
to
be
able
to
Higginbottom
with the 8010 moden is had to read between the
have
two
PETs
connected
by laodera, that could freely talk with each other. I intended to implement this by having a program in each PET which sends characters typed in to the modem, and echoes them to the screen, while displaying any received characters in reverse to distinguish their.r
from the operators text.
The first program that I wrote was based on what I had read in the manual, that if ST (the status variable) is zero, a character is pending and so I wrote a program like this:100
OPEN 5,5
130
GOTO 110
110 GET#5,A$:IF STO0 THEM PRINT" IRVS) "A$" [OFFRVSJ H ; 120 GETA$:IP A$<>"" THEN PRINT#5,A$;:PRINT A$;
This program was totally unacceptable, because dropped 50% of all transmitted characters. However I
read
about
the
SRQ method of
using the
modem.
SRQ
is
it had
the
main reason why the PET IEEE is not a real IEEE-4 88 bus. It is a real line on the bus in the PET, but is not used. SRQ stands for service request, and all it does is to allow a peripheral to tell a controller that it requires servicing. So
the
second
program:-
3 00
OP*7**!
110 120
IF PEEK(59427)AHD128 THEM GET#5,A$ •.POKE 59426,0 iPRIHT" [RVS] "A$"lOFFRVS]"; GETA$:IF A$<>"" THEN PRINT#5,A$;:PRINT A$;
5
5
13 0
GOTO
110
This worked a treat. Line 110 (which is the important cne), says MIF then ::".
Once I had discovered how easy it was to communicate via the GC10, I decided to add a little style. And so the third program evolved frcra my fingertips 20 minutes later. This program uses the window facility of the 8032, and so it will not v:ork on 40 column machines I'm afraid. The top window
displays characters typed locally and the bottom window shows remote activity. I plan to add peripheral transmit and receive file capability, whereby any device can be toggled on or off. This will be published in a future Transactor.
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4
-
8032 Dual Window Modem Communicator
1000 1010 1020 1030 1040 1050 1060
OPEN 5,5:PRINT"IHM HM CLR)" PRINT"ICLR]" FOR I»0 TO 79:POKE 33728+I,64:NEXT CD$="lDN DN DN DN DN DN DN DN DN DN DM DN]" Xl=0:Yl=0:X2=0:Y2=0 SI=59427:MS=128:IO=59426:ZE=0 TL=224:ML«13:CP=198:CL=216:BL=225:HF=232
1080
POKE
1070 LL=80:Sl=3276 8:S2=33808:US=127:BP=ll SI,160:POKE
2000 IF NOT PEEK(SI)
S2,160:ES$=CHR$(27)
AND MS THEN 3000
2010 GET#5,A$:POKE IO,ZE:PRINT"[HM HM]";:POKE HF,ZE:POKE TL,ML 2020 P=S2+X2+Y2*LL:POKE P,PEEK(P) A>JDUS
2030 PRINT"IHM)"LEFT$(CD$,Y2)SPC(X2):POKE HFrZE:PRINTA$ES$; 2040 X2=PEEK(CP):Y2=PEEK(CL)-ML 2050 P»S2+X2+Y2*LL:POKE P,PEEK(P)ORMS 3000 GETA$:IF A$="" THEN 2000 3010 PRINT"IHM HMJ";:POKE BL,BP:POKE HF,ZE 3020 P=S1+X1+Y1*LL:POKE P,PEEK(P)ANDUS
3030 PRINT"[HM]"LEFT$(CD$,Yl)SPC(Xl)iPOKE HF,ZE:PRINTA$ES$; 3040 Xl=PEEK(CP):Y1=PEEK(CL) 3050 P=S1+X1+Y1*LL:POKE P,PEEK(P)ORKS-
3060 PRINT!5,A$;:GOTO 2000
-
5
-
The
Second International
: Commodore
PET
Paul Higginbottom CBM Software Dept.
Show
This was the second PET show, and was much larger then the first. There were ninety three stands comprising of dealers, software houses, electronics specialists, and
systems houses from ail over the world.
foil into packages. Software
The products on show
two catagories, namely software, Each will be discussed below.
and
hardware
Packages
The software packages being shown were mostly accounting packages. Apart from accounting, there were a couple of payroll packages, a few data bases, quite * a few comnunicdtions packages, and other more esoteric areas of software. And of course, the wordprocessing packages VTORDPRO,
and V7ORDCRAFT.
Accounting
software
The accounting packages were all good, combinations of the following features:-Sales ledger -Purchase ledger -Nominal ledger -Integrated ledgers -Open item ledgers -Invoicing -Integration with stock
giving
various
control
I.S.A Computer already have their Commodore in the U.K, name: Ken Marchant)• went up to Bradford
Sevices in Bradford, Yorkshire who package 'THE ACCOUNTANT1, sold by showed me their complete range (contact This was very impressive, and since I for a week while I was working with Commodore U.K, I am aware of their setup, which is also very impressive. They are a data preparation agency as well as a software house with about sixty staff. They have about ten programmers on staff, and are well organized because of their systems experience.
Barthoiemews Business Systems (contact name: Bob Hawthorn) who are a Commodore dealer in the U.K were showing a nev; ledger package that had been taken off a PDP-11 system. This looked good, but I felt that because this show was its launch, it would need field testing before it could be considered. As I have said, there were many accounting packages at the show, and I haven't got time to cover them all here. I.S.A looked the best because of it comprehensive coverage of different options, and the functioning of the package. It also says something about I.S.A when they use their package for
their
own
accountina!
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6
-
payrolls
As
for
to major
payrolls,
differences
well
in tax
they
cannot
be
reviewed
here
due
structure.
Databases
Bristol Software Factory of 'OZZ' fame, who are a leading software house in the PET world (contact name: John Kyle-Price), were exhibiting a new package called 'SILICON OFFICE1. They said "No other package on any computer in the world can offer you as many facilities as Silicon Office" which I felt was optimistic. Anyway, it is a package that has been designed to incorporate data processing, word processing, and communications software into one package. Firstly, it should be noted that this software will only run on the CBM 8096 (a future product from Commodore which is an CBM 8032 with an extra 64K bank switchable RAM) and thus the package will not be available until at least September. It is based around the OZZ package, but does not require the user already own OZZ since it IS OZZ with a whole array of new features. It is now a fully programmable database, allowing 'OFFICE1 programs to be written by the userf or probably more likely, set up by a dealer for the user. It has a built in wordprocessor which can cope with multiple columns of text, expressions to be evaluated out of a data file such as TOTAL VALUE OF STOCK or DEALER PRICE=RETAIL-RETAIL*.3, right justification, automatic centering of text, virtual memory processing for page overflow, stored paragraph or page recall and insertion, horizontal scrolling of text for pages wider than eighty columns, and many other features. However, it seemed to lack the completeness of functions that other dedicated wordprocessing packages have. I thing I really liked was the fact that their were no spurious characters .embedded in the text like, left arrows, reverse field text, graphics symbols etc. as with WORDPRO, and V7ORDCRAFT to a lesser extent. The operation of it worked more on the basis of the format cf the text, rather than where certain symbols were. For example, an empty line of text, or an indented word at the start of a line, signified that the previous line was the last line of a paragraph. The communications software contained intelligent terminal modes driving a modem, with fSilicon Office1 protocols which means that it is probably not very compatible with much else, except another Silicon Office terminal.
They claim that this package will cope with just about any application. My own opinion is that what they have tried to do is an immense task and although it is desirable to try to cover many applications with just one package, what usually happens (and has happened here I think) is that although it may cover a wide range of applications, it does each one in a cumbersome fashion. If I bought 'Silicon Office1, it would be for simple record storage, with selective mailshot capabilities on the wordprocessor, and
-
7
-
because I can have any number of remote work stations that can communicate with each other to produce global reports of (for example) a total inventory report of all work stations, or a current back order situation of a network of •Silicon Office1 stations.
On a final note about this package, I feel that this is a real breakthrough in software for Commodore computers, because of the amount of power contained in one package. This could be make or break time for our applications horizon; whether our computers should stick to smaller, more humble tasks, leaving larger applications to larger systems, or venture onward beyond the capabilities of •SILICON OFFICE1.
Another database product on show was fDMS Data Management System1 from Compsoft (contact name: Nick Horgan). This package has been around for a long time, and was one of the first of the programmable data base products. It is a comprehensive database with calculation facilities, selective reports and utilities to produce files of insertions into text, for both fWORDPROf and •WORDCRAFT1. The length of time this product has been on the market and the popularity of it in the U.K must be give credit to this software house. My only reservations with lDMSt are speed, however record access is quick (two seconds I am told) and in practice; only in a demonstration!
speed
is
not
necessary
Other database products on show were •PETAID1 (Stage One Software), •FILEPROG1 (Amplicon Microsystems), 'OZZ1 (Bristol Software Factory), •THE MANAGER1 (BMB Compuscience). Database software has come a long way since the dawn of the PET era, but they still seem to lack the elegance of something like ■VISICALC1, and the wordprocessing packages such as 'WORDPRO1 and •WORDCRAFT1. 'The Manager1 which is available from Commodore Canada, seems to be the most transparent database product when configured for an application. What I mean is that it seems less like a database, and more like an applications package, when configured, than the others. •SILICON OFFICE1 will be by far the most powerful database product available in the world, when it becomes available. Communicat ions
Software
There were a good number of communications packages which proves the potential of this marketplace. Rod Welburn is Communications Manager of Commodore U.K and he feels that there is a huge potential .in using the CBM 8032 as an intelligent terminal. This is true, primarily because of the price of the 8032 as compared to any terminal (dumb or smart). Provided the software is comprehensive and flexible enough to cope with the numerous protocols involved with talking1 to different machines, Commodore could be onto a winner.
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8
-
CORTEX
(contact
name:
Howard
Johnson)
are
a
software
house which deals only in communications software and a package of theirs called 'COMMUNICATOR1 is a Commodore product in the U.K, The software they had on show was very goodf especially due to the fact that their package allows a CBN-to communicate with an IBM computer! Kingston Computers is a Commodore dealer and deal primarily with network systems for CBM computers. Their product NETKIf allows any number of CBMfs to talk to one another, and/or a mainframe. Their were not be covered. Other
other
packages
at
the
show,
but
these
need
Software
Claremont Controls (contact name: Roy Stevenson) is a Commodore dealer who specialise in constructional software. They are the best in this field. Final
note
on
software
Of course, •WORDPRO1, and 'WORDCRAFT-1 were both on show. They were side by sider which was interesting in itself, and it seemed as though each stand was trying to print more •demo1 letters, than the other! Hardware
Apart from numerous interfacing gadgets, D to A, and A to D converters and multi-port boards, the big steals of the show were the hard disk drive, and a CPM operating system. MATOR HARD DISK - This is a 10, 22, or 3*5 megabyte hard disk. The DOS they are writing for it will be compatable with existing Commodore disk units. It was connected to the PET by an RS-232 interface at the show, but there will also be
an
IEEE
version.
CPM system - For those not familiar with CPM, it is a small operating system less powerful than the CBM Kernal, but immensely popular on 808X, and Z80 machines. Because it has been around a very long time, there is a mountain of pre-packaged, good quality software for it. This implementation for the CBM is by means of a 'black box1 that is attached to the memory expansion port, which contains a Z80 micropocessor. HI-RES
excellent
Board
product.
for
^
It
the
is
a
8032
from
flexible
good supporting software to go with graphics on a matrix up to 512 X 512.
Commodore
graphics
it.
It
U.K
system
allows
-
An
with
pixel
General
In general r I felt that the show had an enormous enthusiasm from both visitors, and exhibitors* Commodore's own stand was "massive, and well presented* There was a VIC-20 ARCADE, which consisted of rows of VIC's lined up with joysticks, and televisions above, sealed in a presentation casing to prevent theft. These had games on them which were exact replicas of familiar arcade games such as 'PACMAN1, •INVADERS1, 'GALAXIAN9, and 'RALLY-X1. This was contantly occupied by thousands of children (big and small!) • To the right of the arcade, along one wall, was all the packaged
software
products,
hardware products
and * along
the
other
wall
was
including the CBM cash register.
all
the
Jim Eutterfield (I had to mention him somewhere), was mobbed wherever he went, and his seminars had five hundred people in a room big enough to hold fifty.
I felt that the level of expertise was high but still there are so few 'visicalc-wordpro-wordcraft1 type of products, which are the kind that really do well. Accounting
packages that are taken off larger machines is definitely a good approach to getting a system that incorporates the necessary options, and flexibility.
where
As the PET world gets ever bigger, our expectations it will all end, get blown apart each year.
Probably by Albert Hall for the
next show!
year,
-
10
Commodore
-
will
use
of
the
Video Interface
Ted Eversf
For 4 0/80 Column PET/CBMs
The purposes
Toronto
-Metro Separate School Uoard
demand for a. larger display for demonstration and classroom user prompted a search for a video
interface between
we had a plentiful As there were
the
PET
and
supply
an
external monitorr
in our school system.
several
designs
already
of which
available
in many
publications, we decided on a modified version, of a circuit', originally published by R.
S.
McLean, MECA,
The main design criteria of the system was, 1.
be simple to build,
mainboard
OISE.
it had to:
install and wire to the
2. 3. 4.
be easy to service have no interference with other plug-in devices be compatible with both the high-base and low-base
5.
have standard output-connectors for both video
type chassis
and audio accomodate our "DUKP" system at a minimum of extra cost, when so required*
6.
To meet the set requirements, we decided on a printed circuit board design, measuring 2 1/2" x 3", this to be mounted by means of one #8 machine screw on the inside of the rear base apron, just above the user- and cassette-ports. A template was laid out for the hole locations to accommodate the BNC type video connector, the RCA type audio connector, the mounting hole for the P.C.B. and if so required, a DIN type connector for our "DUMP" system.
the
The
circuit
diagram
is
fairly
six inverter/drivers available
straightforward.
in the 7406
I.C.
Four
are
of
used
in the video interface to combine the vertical and horizontal drive pulses with the video signal to obtain the required composite video.
The fifth inverter isolates the CB-2 line from the outside world, while the "DUMP" is activated by the last inverter. The input, of this driver is connected to "E" (SAVE) of the cassette-port from the master-computer, while the output goes to "D" (LOAD) of up to 20 slave-computer units. Removing R8 and grounding "DUMP"-input will deactivate
60
this
By using an slaves can be
feature.
additional driving loaded at will.
unit
("DUMP-HATE"),
up to
A minor board modification and component change will make the design suitable for the CBM 8032 video interface. However, the audio will have to be connected directly to the CB-2 line and no dump is possible.
-
11
-
Editor's
Note
The "DUMP" system mentioned is an interface that allows 20 slave PETs- to download from a master PET using the 1st cassette port. "DUMP-MATE11 boosts slave capacity to 60! Hoth circuits will appear in the next Transactor with modifications to make it compatible with the 8032 and the new "fatw 4032 which, by the way, also uses the 8032 video interface.
Included in the following diagrams is some circuitry for ir.aking Electrohome ETV-6 and ETV-7 video monitors switch-compatible for either 40 or 80 column interfacing. If operation with both 40 and 80 columns isfnt necessary, then
simply adjust the proper potentiometers in the ETV-6/7 and change the screen voltage to the horizontal output tube to obtain the proper width. 80/fat40 column operationmay require this to bring down the vertical and horizontal
dimensions,
however with the 9" 40 you may not need it.
The 8032 interface board has a wire running along side the 7406. This connects pin 1 to pin 6 of the 7406. To get a "picture" of the final product, try super-imposing the component layout diagrams onto the artwork for the printed circuit board.
-
12
-
mirror
image
of
the
3.00
inches
-
13
-
lerbni
00.
AV-&10I
Bo»*O
-
15 -
Zooi).
-2oo/~
fiV-6101 PET
2001
H K A R
DRILLIMC
iPBOd
TIHPLATK
"IDP-DGP
VIDEO (BNC)
AUDIO (RCA)
Hole site:_ 3/6*
Hole sise:
SUMP (DM)
l/4-
Hole B^e;
5/B"
Drill only when requ Ted,
'I
■LEFT-faDJ-IDGE"
/'/*"
P.C.B.-M0UNT1NG.
(
Cassette-port.
Hole eixe:
use Ho. 19 drill.
)
(
P>rallel-MBeiwport.
CQKPOKENT-RBQUIRPffiKTS:
BNC-CONNECTOR
i
Anpkenol
RCA-CONNKTOR
i
Switckcraft
GROUND-LUG
:
Anphenol
t HABDUARX
*
Prek
: * 2 Jtf
2 .1
Note:
31-236
(UG/U-625B)
35OL-PP
31-759
71200-050
4-40
nackiae screws (1/2" for DIN rant)
4-40
nwts
S-32 X 1*
(for DIN aount) Bachine screw.
1
No. 0 wasker.
2
8-32
Only required,vfee» *ftJKPt i» msed.
-
16
-
~c-
— 20Ot~
W-Btoi ..
&
VIIM
PORT
8OKNBCT AND SOLDiB APPKOPKIATB LKADS FROM THE AA-INTUIFACS BOARD TO THESE PADS.
THLM KXCKSS LKADS AND CHECK FOR SHORE,ETC.
3.
fy £
2.
V
CASSBTTS
-r v
*
Pit 2 0 •'! -"C 0 HPQHiH tSIDI
PORT
.
HSHUVS SOLDiB PROM THE SIX INDICATfD PADS,
USER
.
1.
PARALLEL
,
- Zooi-
'"Top-
Video
p.c.e>.
£
• BASF.
- 18 -
For
TO To
V911 /
T0V5" ♦ frv
Vioeo
-10-
To'Z
C1M
tIAlt
8 0
D It I L L I M G
-80&Z-
APftOM
TIMPLATI-
•LEFT-SIDM
VIDE) Dole slse:
AtDXO (1CA)
(BMC) 3/8*
Hole lise:
1/4
P.C.B.^10UNTUC.(-f)uole site: mse Mo.19 dri] 1.
Cassette-port.
F»r&ll el—
CCMPOMiM T-HJCUIRBCSKTS t
BNC-C0NNK7DR
Aapkenol 31-236
BCA-CQNNiCTOR
SwltckcraTt
GROUND LUG
(0G/U-625B)
3501-f^.
Aaphenol 31-759.
1
8-32 X 1/2* machine screw.
1
No. •
2
8-32
n«te.
rt
3.
2.
1.
U S K R
"2"
**NN
"M-
"9E
AND "10" ,
TRIM IsJLCESS LEADS AND CHECK FOR SHORTS,ETC.
W1R1S TO THE ENDPART OP THE CON TACT-
AS THUW ARS NO PADS POJ1
PORT
BB VERT CARfiFUL WON ATTACHING THESE
CONNECT AND SOLUKK APPROPRIATE LKAUS FKOM THE INTtltfACE BOARD TO mSI PADS*
"B"
?IIN
C A 3 3 IT TI
CBM6O32"COMFONBNT-SIDE"
FORT
KEHUVJt SOLDER FROM PADS "A"
PiHALLEL
-80ZZ-
ta ar
Rc.e>.
QLTEGNATE
TtfipLArF
FoR
- 22 -
.
O
0
4:
CONNECT »C" TO T5-U (2) AND •A" TO T3-U
IT TO THI NOH VACANT TS-U (2).
DISCONNKT R-715 PKM T3-U (6) AND
»
3t
O
OONNKT IU71O and C-708 TnCKTHBl IN MID/i
Q
at
O
RIM0V1IU71O and C-708 FROM TS-U (2).
♦
It
TS-U
AND WATTAGE RATING TO OBTAIN + 13$ VOLTS,
R-502 WITH A RESISTOR OP SUPnCIBfT VALUB
IP IT MIASUNB BELOW + 1}O V0LT5,SHUNT
CHECK THK UVB. OP THI "B+» SUPPLT.
WO T I I
2 i
PoftT oP
HoR. OSC.
Part ftc HeR.Qufr
"C
?5
KHS \Jt>lll
8o-
HpoiFic/m o n $
W I B I M C .
lA
I
B
1
C
Id
1
E
1
F
1(3
1
H
1I
Ij
1
K
1
I N e
1:
INSTALL 220 X.OIM RESISTOR BET
2:
INSTALL
3:
INSTALL DIODE (UUtOOl)
4:
INSTALL 150 Oltt
5:
CONNECT
"A"
10+250 VOLT SUPPLY.
6:
CONNECT
"B»
TO ♦ 135 VOLT SUPPLI.
7:
CONNECT
"C"
TO TS-U (2). (Note:tS-Ushould hare been nodified as per) (page 1 instructions.) t
6:
CONNECT
"D" AND "I" ACROSS R-606.
9:
CONNECT
"G" AND *H» ACROSS R-707.
10: CONNECT
■i"
AJ©
22 K.OIM RESISTOR BETWEEN "G"
AND
"I".
BETWEEN »N"
AND
•«". {Observe polaritj)
BSSISTOR BETWEEN "X"
AND
"J".
»J»
10 * 27 VOLT SUPPLY.
11: DISCONNECT ALL WIRING FROM SW-203. (Audio-filter-switch on front panel) 12: CONNECT CENTER CONTACT OF SW-203 TO GROUND.
13: CONNECT "ON* CONTACT (rear connection) OF SW-203 »
•*" OF BELAY.
14: SOLDER ALL CONNECTIONS AND INSPECT WIRING FOR PROPER DRESSING*
-
25
-
m
a*.
Mm.- mltx
J-j
9
m
CT« JL»C$T i
-
26
-
H0/&O
i
CtCS
±«?
I
W MOK
fk • 4f:
* OPT
•lOf
h?
~7t:. «»•!
•oosi
-
27
n~7.
-
\
ctif _
f
3
i h
3
o
i 1
o
Ji
rr._ o
-i
I
NEW DIAL-A-ROM models
from
KOBETEK
SYSTEMS
LTD.
It has now been over a year since we first introduced the Dial-a-ROM.. At that time, there were not too many chips around (V7ORPRO and Toolkit). In the past months, however, there has been a steadily increasing number of various utility and protection ROMs. There is also room in the VIC expansion board for two 24-pin ROMs. He suspect therefore that the nunber of (P)ROMs will grow at an increasing pace.
The Model 6H Dial-a-ROM has room for 6 ROMs. It comes equipped with a flat ribbon cable, at the end of which is a 24-pin DIP plug that fits into one of the two empty sockets on the BASIC 4.0 machines (4016, 4032, 8032, VIC). Because of its design ( the 6-socket board is housed in a plastic cabinet that sits next to the machine ) , the flat ribbon cable will not interfere with any expansion boards that you may want to fit on top of the motherboard. The only thing that goes into the computer is the plug. The model 6H has a 6 position rotary switch on the front, which allows you to select one of the 6 ROM positions inside. Note that only one ROM is selected at one time. Also all ROMs
inside the unit must be addressed at the socket into which you have put the plug (unless you move the plug to the other socket).
The model 33H is for those people that don't need room for 6 ROMs with the same address. It also has 6 sockets, but they are electronically grouped in two groups of 3 (or in a group of 2f and one of 4 - the user decides by means of a jumper) . The 33H also has a flat ribbon cable with a dipplug, and has a second cable with a socket at the end. The dipplug goes into one of the ROM sockets on the computerboard, and the cable socket goes into the other. The 33H has 2 6-position rotary switches, one to control each of the sockets. It permits two ROMs to be selected at the same time, one in each of the ROM sockets of the CBM. The model 66H is for those who donft need room for 6 ROMs with the same address, and also have no need to have two ROfls active at the same time. This is probably most of us. The 66H has a dipplug cable and a socket cable like the 33H, i.e. one unit will do for both of the CBM sockets. A toggle switch on the front allows you to select one of the two CBM sockets. You then dial to the position of the socket in the 66H which contains a ROM addressed at the selected CBM socket. The 66H offers the user complete freedom in the mix of ROMs in the unit to a maximum of 6.
need tied
In the works: The 11H, a daisy-chained model for those who more than 6 ROMs in the same socket. It is a pair of 6H's together, with its own power supply. Prices
(Canadian funds) Model Model Model
- Please
add
66H
For more information contact Sieg R.R.#1, Wolfville, Nova Scotia, 902 542
29
airmail
post
115 .00 135 .00 135 .00
6H 33H
-
$ 5.00
-
Deleu 9100.
at
Kobetek
Systems,
JOYSTICK/KEYBOARD ROUTINE
David Hook,
Barrie Ont.
purpose;
Many programs, especially games, allow the user to control movement using the numeric keypad* Usually, pressing >8' means 'up1, f2' means 'down1, '4' means fleft' and '6' denotes •right1• Diagonal movement is also permitted with the 1,3,7 & 9 keys. The middle of the keypad, 5, signifies no movement or no change in movement. In games, the 'SPACE1 sometimes
indicates a
'fire1
button.
Since I have produced a joystick great to have a single program work keyboard input.
interface, it would be for both joystick and
The program will work on all three ROM versions easily incorporated into new and older programs.
and
be
Description?
Combining a test to screen out all other keys, and decoding the keys takes a fair bit of coding. Fast animation is sometimes restricted by the processing time involved.
Wouldn't it to handle all of a simple command
be useful to have this. The routine and ignore all but
a simple 12-line program should be initiated with the "desired11 keys. Such
as...
50 60
N=USR(0):IF N=0 THEN 2000 ON N GOTO 100f200r300,400,500,600,700f800,900
Thusf the variable N takes on values 0-9 only. Zero corresponds to the 'SPACE1 key. All the others can be handled as their proper direction. No other keys will affect •N1. N=5 when no key has been sensed* This could be programmed to mean no movement, or as no change in direction.
The same input to 'N1 is connected. Now the '0' reflects JS/KB
made when the joystick is the 'button' being pressed.
LOADER:
Enter the 14-line program as in Save it immediately, as a precaution "crash". RUN
the
the listing provided. against an accidental
program.
The program loads a short Machine Language routine (93 bytes) into the first cassette buffer. Even if you are loading from Cassettetl, the routine should be safe there until you load another program. The USR vector will be set
according to your answer to the "using joysticks11 question. Any time you enter
an expression...
variable=USR(O)
•••the routine will be invoked assume the value 0-9, as above.
and
the
variable
will
Line 13 in the program is a quick test of the program. Hold down each number key as it's running* Hold down the 9SPACE1 key also* Note the numbers appearing on the screen as it runs* Both Line 0 and Line 13 aren't necessary when you come to use the program* It shouldn't be too difficult to modify existing Basic programs to incorporate the dual functions*
While you are at it, consult Compute #4 or Best of Pet Gazette* I've had only a passing acquaintance with a soldering iron. My joystick interface works great with the above routine* Trying the four Cursor joystick-compatible programs is another challenge* Modifying five versions of Space Invaders (old, 2*0 normal, 2.0 fast, 4*0 normal & 4*0 fast) is another tale* You can find these at any of three Toronto PET dealers. Note to hackers: I've selected the 'SPACE1 as the 'fire1 button* If you want another, change the ninth data item from '32' to the ASCII value of the key of your choice. Source
included.
code
for
the
MAE
-
or
31
ASSM/TED
-
assembler
is
also
PAGE
0090 0100
0110 0120 0130 0140 0150 0160 0170 0180 0200 0210 0220 0230 0240 0250 0260 0270 0280 0290
027A027D027F0281-
028302 8502 870288-
02 8A028C028E-
20
E4
C9 F0 C9 DO A9 38 E9 30 C9 30
30 OF 20 02 30
0290- A9 0292- A8 0293- A2
FF
0300 0310 0320 0350
0360 0370 03 80 0390 0400 0410
.CE *
JOYSTICK/KEYBOARD ROUTINE
DAVID A.
HOOK,
9* }*
USRPORT
GETBYT KEY1
KEY2/4
INTFLP1 INTFLP2 INTFLP4
KEYBD
.DE .DE .DE .DE .DE .DE .DE
$E84F $FFE4 $0203 $0097 $D27 8 $D26D $C4BC
.BA
$027A STORE
CMP BEQ CMP BNE
#'0
NOTSPC
#'
#'0
0440 0450 0460 0470 0480 0490
CMP
#10
BMI
HAVKEY
NOCHG
LDA
#5
HAVKEY
TAY
;SAVE
;ENTER KEY VALUE OF IN R(Y) ;=
;1.0=$FF
2.0=$00
BPL
;FOR
2.0
;MEANS
NO
KEY
PRESSED
;MEANS
NO
KEY
PRESSED
STX
KEY1
JMP
USER
02A0-
0520 0530
STX
*KEY2/4
02A2-
4C B4
02
0540
JMP
USER
E8
0550 0560 0600
LDA
USRPORT
NO
KEY
'5'
#255
0510
4A
IT
KEY
ROMTYPE NOT1
02
02AB-
;WRONG
LDA
02
JOYSTK
;SPACE=BUTTON
LDX
03
0610 0620 0630 0640
KEY?
SEC NOCHG
NOT1
1.0 2.0 4.0
IN FIRST CASSETTE BUFFER
;SPACE
SBC
0500
JOYSTICK
,-ZERO KEY?
NOTSPC LDA #'0
BMI
4F
*
NOCHG
8E
4A 4A 4A
*
JSR GETBYT
4C B4 86 97
AD
.
726-8126
INPUT FROM USER PORT FOR GET A BYTE WHICH KEY—ROM 1.0 WHICH KEY—ROM 2.0 & 4.0 INTEGER TO FLOATING—ROM INTEGER TO FLOATING—ROM INTEGER TO FLOATING—ROM
029D-
02A802A902AA-
*
*
029A-
02A5-
ONTARIO
.A******************************************************
0430
02
(705)
BARRIE,
;*
0420
FF
58 STEEL STREET,
L4M 2E9
04 OA 02
0295- AD C6 0298- 10 06
* *
;*(C)
30
05
01
ROM
PRESSED
;GET JOYSTICK
;DIVIDE BY
LSR A LSR A
S,
4.0=$01
4.0
BIT
PATTERN
16
LSR A LSR
A
AND
USRPORT
0650
02AC- 2D 02AF- A8 02B0- B9
02B3- A8
4F C7
E8 02
0660 0670 06 80 06 90 0700 0710
TAY LDA
TAY
;KEEP VALUE JS.TAB,Y
;LO BYTE
;USE
FOR
INTEGER
AS
INDEX
CONV
TO
KEY
VALU
PAGE
2B4-
2B62B92BB-
2BE-
2C02C3-
A9 AE 10 4C DO 4C 4C
00 C6 03 78 OS 6D BC
02
D2
0720 ; 0730 USER 07 40 0750 0760
D2 C4
2C62C7- 05
05 05 08 03 2D3- 05 04 2D6- 05 2CA- 00 2CD- 09 2D0- 01
05 07 05 02 06
,ABEL FILE:
0770 TWO/FOUR
07 80 0790 FOUR 0800 ; 0810 ; 0820 ; 0900 ROMTYPE 0910 ; 1000 JS.TAB
1010 9995
02
LDA #0LDX ROMTYPE
;HI BYTE FOR INTEGER COKV ;1.0=$FF 2.0=$00 4.0=$01
BPL TWO/FOUR JMP INTFLP1 BNE FOUR JMP INTFLP2 JMP INTFLP4
;TO FLOATING
FOR 1.0
.DS 1
;1.0=$FF 2.0=$00 4.0=$01
;TO FLOATING FOR 2.0 ;TO FLOATING FOR 4.0
.BY 5550579851325465
; .EN
I / - EXTERNAL ]
'USRPORT=E84F
KEY2/4=0097 'INTFLP4=C4BC IOCHG=0290 rOYSTK=02A5 .'OUR=02C3
/GETBYT=FFE4 /INTFLP1=D27
/KEYl«0203 /INTFLP2=D26D
KEYBD=027A HAVKEY=0292
NOTSPC=0287 NOT1=02AO
TWO/FOUR=02BE
USER=02B4
ROMTYPE=02C6
JS.TAB=02C7
V0000,02D7r02D7
-
33
-
What
Hardware
do
I
Have?
7irc Bctteriield,
Toronto
Users used, to tell their PET/CBM machines apart by the size and shape of the keyboard, or by the message that was displayed when. power was turned on* That doesn't work too well any more* New keyboards can be fitted to old machines; new ROM sets can be plugged in; and even the green screen/white screen isn't much of a hint any more*
Although I'm not a hardware man, I often get calls from users who want to know about some aspect of their machine* I try to establish which machine they are talking about.
Commodore may have a much more official checklist for their hardware configurations: but here's the set I use. Perhaps readers can suggest other differences that are worth while knowing*
Items
1
and
2
are
pretty
obvious:
how
many
columns
on
the screen - 80 or 40 - and what type of keyboard* Ifro not concerned with tiny versus full-sized keyboards; rather, is it a simple graphics keyboard or a full-scale business ASCII layout? The easy way is to look at the top row, above the alphabetic letters: are there numbers along the top or just symbols? The next question: does your PET have original architecture or the more recent layout? The tipoff here is the connector on the right-hand side of your machine. If you see an edge-connector - a connector with copper "fingers" extending from the board inside you have the original machine board. On the other hand, if you can see a series of upright pins when you peer through the right hand slot, you have a more recent board. Another way of telling the same thing is to type POKE 59409,52. If the screen goes blank when you press RETURN, you have a unit with original architecture. Here's another characteristic of the early machines:
if you type FOR J=l TO 1000:POKE 32768,0 :NEXT J there will be a lot of "snow" on the screen for a few moments; newer machines don't have this problem.
The next thing to test is the screen writing speed. Clear the screen, and type on the top line or two: TI$="000000":FOR J=l TO 600:PRINT "A"; : NEXT J: PRINT TI$ and press RETURN. You'll get a lot of letter Afs across the screen, followed by a number. If the number is 000002 or less, you have a fast screen machine. If it's bigger, you have a slower screen unit. Don't worry the speed difference is only seen when writing characters to the screen, and you can't read that fast, anyway.
There are a couple of minor cosmetics that are sometimes worth noting. Do you know which cassette unit plugs into the back connector? Is it cassette number 1 or 2? There1s a difference in board wiring either way. And finally, if you like rummaging around the inside of your PET, how many pins do
you
have
on
your
ROM
chips?
-
If
34
-
you
don't
know
how
to
spot
a
ROM"
Cnipr
you
uuu
u
uccu
While you have the lid open,
uw
iw«v~
*..-
. .
count the number
of ROM sockets.
There are other hardware differences that you'll find in various PET/CBM machines, but the above are the ones I ask for most often. Technical tyros will be glad to add to the list: what kind of RAM is fitted? How are the ROM sockets decoded? ♦• and so on. Many other differences that we notice between machines seem to be hardware, but they1re really software, It's quite surprising how different logic can make the machine appear physically different. We111 talk about spftwarer or ROM sets, a little later. Some people claim that cosmetics make a great deal of difference to a computer's usefulness. I suppose it's part of your state of mind. I've seen PETs with racing stripes and others with pink polka-dots. If the owners feel that they can write better programs that way, good. I'm thinking of painting one of mine puce-coloured in the hopes that it will keep the
cat away...
What
System?
Software
There are (at time PET/CBM software ROMs.
of writing) three general styles of ROM stands for Read Only Memory their programs are set at the factory and cannot be changed. That's OK - few of us have the talent and/or ambition to change the internal workings of our PET/CBM system, and even if we did we'd lose one of the great advantages of the home computer: the ability to exchange programs with others. The ROM programs, being pre-written and burned in, are there the moment we
turn the power
on.
I call the three generations of Basic: Original, Upgrade, and 4.0. The first two generations had confusing number systems: some Commodore divisions called Original ROM sets Basic 1.0; others called the same thing Level 2 Basic. When the Upgrade system arrived, the numbers changed to Basic 2.0 and Level 3 so as to make the confusion one hundred per cent. By the time 4.0 Basic came along everybody synchronized, and the machine prints BASIC 4.0 to end the problem once and for all.
Within each Basic version, there are small differences to accommodate variations in the hardware. The Business or ASCII keyboard - the one with numbers across the top row needs to be scanned in a different way than the graphics keyboard; and 80 column screens must be worked in a style that differs from the 40 column display. These differences are reflected by changing one ROM out of the set to allow for the configuration desired. The other ROMs in the set are the same regardless of hardware.
-
35
-
The first Basic came as part of the Original ROM set. It had a lot of limitations. You couldn't put more than 256 itens into an array; you couldn't do a successful IEEE-488 input; you had no machine language monitor; tape data files had potential problems. Most users breathed a sigh of relief when the newer Upgrade system became available.
If you have Original with the message: *** cLt^risks: they are the
ROM Basic, your PET will power up COMMODORE BASIC ***. Note the signal that you have the Original
system.
If you have this early Basic, it's worth while thinking about moving up by obtaining a replacement ROM set* You'll get technical benefits* More important, you'll be joining the mainstream of PET/CBM users and be better equipped to exchange ideas and programs. Upgrade ROM solves the above limitations. Users with Upgrade ROM will see ### COMMODORE BASIC ### when they turn the power on. Whether you call those symbols pound signs, number symbols or hash marks they clearly flag Upgrade ROM.
Users with original hardware can refit their machines to Upgrade ROM, but they will have trouble in taking the next step to 4.0. It's not just that they are missing the ROM socketing to plug everything in: they would also find that screen "noise11 would start to give trouble. Basic 4.0 doesn't politely wait for the screen to be ready before delivering new information .,, characters are slapped in at full speed. Newer machines won't see any problem, but the original boards may end up with a screen that looks like a snowstorm.
the
The newest Basic screen announces
useful, but things like better file collection,
so far is 4.0 and it's easy to spot: the number. The changes here are not essential. You get new commands for disk: DLOAD, CATALOG and SCRATCH. You get somewhat handling; and that great time-waster, garbage has been speeded up so that it is no longer
annoying. cosmetic;
In many respects, they support ease fundamental road blocks.
the 4.0 of use
improvements are largely rather than eliminating
There's great compatibility between the various versions of Basic, especially between Upgrade and 4.0 ROMs. Each user tends to exploit the features he is givenf however, so that programs on a time-travel back
Still,
they
more recent model to earlier versions.
are
all
PETs.
-
They
36
-
may
all
not
have
be
that
able
style
to
...
The- Fat
40
A New Generation
Therefs
fanfare or
a
40
Column
new kid
Jim Butterfielo
PET
Toronto
on the
block.
It
arrived without
any
advanced publicity:' the Fat 40 - a large-screen 40
column PET.
The most noticeable feature of the fat 40 is its big 12-inch screen. You'd almost think you had an 8032 80-column computer until you look at the keyboard and notice that the keyboard layout is graphics rather than ASCII business. When you turn it on, the screen characters come up fat and crisp. I'd heard that Commodore would be fitting 12-inch screens to their 40-column computers, and had thought that this would be only a screen change. Most of us, I think, were unprepared for a noticeably new machine with new logic. The logic board has changed so that it is similar in layout to that of the 8032. More importantly, the program logic has been changed so that we have more than a new size of machine: we have a new style. The changes are improvements, but we'll have to recover from the shock of having a new system introduced with no advanced fanfare. Host programs which work on the skinny 40fs will move to the fat 40 without trouble; I'll try to itemize possible conflict areas later in this article. A Junior
80?
The fat 40 picks up much of the style of the 80 column machine. In fact, many of the features of the 8032 are now available in 40 columns, including ringing the bell, erasing part or .all of a line, and screen tabulation. Windows - the
ability
to
scrolling,
pick
out
are not
a
piece
of
the
screen
-
and
up/down
available.
The user will notice one of the features right away - as he turns the machine on, a bell chimes. Yes, there's an electronic bell in there, and it chimes any time you get near the end of a line. You can make it ring from your program with PRINT CHR$(7). The bell may be turned off or changed by poking the contents of location 1004 decimal - note that this is a different location from that used in the 80-column machine (231 decimal).
keys.
Another feature that's The cursor movement
hard to miss is keys, the Space
Insert/Delete key repeats automatically down for a moment. Very handy. The user may switch to Text mode
if
the repeating key, and the
the
key
(upper/lower
is
held
case)
with
PRINT CHR$(14). This is easier to remember than the POKE address, and gives you another bonus: the screen lines are readjusted to give you somewhat more pleasant text appearace. You may return to graphics with PRINT CHR$(142) .
-
37
-
There are commands for clearing all or part of a line; it takes a little dexterity to get them to work right since you must carefully place the cursor before using them. To clear a line, up to but not including the cursor position, PRINT CKR$(150). To clear from the cursor to the end of line,
type
PRINT
CHR$(16) .
This
appears
to
be
a
error
on
Commodore's partr since PRINT CHR$(22) does the job on the 8032 and is more consistent. It seems as if someone has confused decimal 16 with hexadecimal 16 (22) in the coding. I would anticipate this being corrected in future ROMs; in the meantime, you can print both characters and create programs which will move gracefully through any such future correction: PRINT CHR$(16);CHR$(22). This Erase-to-End sequence is often very handy: it allows you to clear a line before printing
on
it.
Screen tabulation is included. It will probably be less useful on a 40-column machine as compared to its 80-column big brother, but it's not hard to use. Set or reset tab positions by positioning the cursor and then printing CKR$(137) . You can move to the next tab location when desired by printing CHR$(9).
System organization
changes.
Users who fiddle with the innards who have programs that do so - should internal changes in the fat 40.
of be
the machine - or aware of certain
The keyboard is decoded in a different manner from previous 40-column machines; you should not depend that PEEK (151) will give you the same values for specific keys being pressed. You may still expect that this value will be 255 if no key is pressed - but the other values will have moved
around.
The Screen Wrap table, which tells us which rows of the screen are joined together into double lines, is still in the sane place. But this means that some of the 80-column variables needed to be moved clear of this area; values previously stored to the area 03E9 their functions, locations alone, operation.
in locations E3 to E8 have been relocated to 03EF. You don't need to know all of but you must leave these new address or you'll interfere with screen/keyboard
80-column tyros might wish that all the wide screen features had been implemented on the fat 40. It probably wasnft possible: the two machines need to be organized differently. Users who go looking for the 80-column screen windows or for the input and output vectors will be disappointed: they aren't there.
-
38
-
Sumnary*
It's an exciting new machine.
and should be very convenient* told us it was. coming ... btit
I in
here.
-
39 -
It has good new features^
wish that Commodore had any case, I'm glao it s
The SUPERPET:
Introduction
A First
Joseph P.
CBM
Ferrari
Software Dept.
.
The dawning fast
Look
of
approaching.
a new age The
in the micromputer
announcement
of
the
industry
is
SUPERPET Computer
by Commodore has demonstrated that a new breed of micros is on it's way. With 5 languages currently available and a whole lot of RAM spacef it makes the SUPERPET one of the most versatile
computers on the market
today*
Although the SUPERPET has not yet been released, I was able to get my hands on one of these beasts for testing and evaluation. Since it is a pre-release version, all information contained in this article is subject to change* There is a lot to be said about the SUPERPET, but I will discuss mostly Waterloo microBASIC and its features. Powering up the SUPERPET comes up the usual Commodore Basic, but by flicking a switch located on the bottom right side of the computer will bring up Waterloo microsystems menu. All the languages available are boot-loaded from disk, with the exception of the monitor which is resident in rom. Selecting b will load Waterloo microBASIC with 30150 bytes Editor
free. Features
For those of you who frequently use a developer's toolkit, you will be pleased to know that Waterloo microBASIC includes the following features in their editor for the
development A)
of
programs.
DELETE
B)
RENUMBER
C) D) E)
AUTOLINE MERGE STEP
Debugging
Programs
Here is one feature that I really like. When a program been interrupted either by the opperator or due to an error in the program, changes or modifications can be made and execution of the program can continue at the point of interruption or at any loaction desired without the loss of the current variables. has
Saving and Retrieving
Program
Files
Unlike Commodore basicr Waterloo microBASIC gives options on hov; a program can be saved and retrieved. 1)
STORE
-FILENAME11
Will output the program to the disk in a compressed Tv;o advantages of saving programs in this manner arc: a) b) 2)
two
fern.
occupies less space on disk faster in storage and retrieval
SAVE
-FILENAME"
Will save the program as it is typed on the keyboard anC will appear on the directory as a sequential file. This method should be used only while the program is under development. The advantage of this mode is that portions of the program can be saved and eventually merged with other programs by specifying a line range.
3) Retrieves command
4)
LOAD
"FILENAME"
program
OLD
files
that
were
with
the
•STORE1
"FILENAME11
Will load a program file that command. Any existing program new program is then loaded. 5)
-saved
MERGE
was created with the 'SAVE1 in memory is cleared and the
"FILENAME"
Adds the program specified to the existing program in memory. Be very carefull when using this command, for any nev; line number comming in that exists in memory will be deleted and
the
new line
String
inserted
in
its
place.
and Variable Representation
If you have ever encountered a point in program development where you can't think of an appropriate name for a variable, in nircoBASIC you won't have such a problen; because all string and variable names can have up to 31 characters with upper and lower case representation.
-
41
-
Repetitive
Structures
VJaterloo
microBASIC
supports
a
variety
of
statements
that make coding easier to implement and also much easier to understand. Since we are* all familiure with the FOR-NEXT
LOOP structure, I will may or may not know*
skip it entirely
and go on
to
some you
UHILE-ENDLOOPS
Delimits repetitively
a if
group of the value
statements to be of the expression
executed is true
(non-zero) Fxample-
X=15 WHILE X PRINT X X=X-1
ENDLOOP
The example above will execute statements starting with WHILE and ending with ENDLOOP until the value of variable X is equal to zero. As you can see ENDLOOP is similar to saying GOTO only without specif ing a line number. As a point of interest, VJaterloo microEasic executes much more efficiently with
structured
loops
in
comparison with GOTO
statements.
LOOP-UPTIL
Delimits a group of statements to be executed repetitively if the value of the expression in the UNTIL statement is true (non-zero), control is then passed to the statement immediately following the UNTIL statement. ExampleX=15 LOOP PRINT
X
X=X—1
UNTIL
X=4
LOOP-EKDLOOP
To
Defines a group of exit loop, the STOP
IF-THEN
statements to be repeated infinitly. key is pressed or by introducing an
statement.
Exair.pl eX=0 LOOP PRINT
X
X=X+1
IF X=10 EDDLOOP
THEN
QUIT
Execution of the statements falling v/ithin LOOP and EKDLOOP will be repeated until the value of X is equal to 10* Control is then passed to the statement following ENDLOOP.
-
42
-
ir-Tiini:-ELSE
Host of*us accustomed to Commodore Pasic with the IF-THEN statement. MicroBASIC offers to this statement with the ELSE option. stcterccnts following ELSE are executed if the false. END IF delimits the ELSE statement group.
ore familiar an extension The set cf condition is
Example-
COOKTER%=1 LOOP
TESTERS, = INT (COUKTER% / 2)* IF TESTER% = COUKTER% PRINT COUNTERS, "NUMBER
IS
2 EVEr"
ELSE
PRINT COUNTERS,
"NUMBER
IS ODD"
END IF
COUNTER% = COUNTERS+1 IF COUNTERS= 10 THEN QUIT ENDLOOP
The above example demonstrates the power of the ELSE option with the IF-THEN statement, especially if more than one statement is to be executed in each condition. I ir.ust say that utilization of structured coding makes for far n.ore readable
code.
Although there are many more features that I have not covered in this article, I hope that it has given you a small taste of what to expect with Waterloo microBasic on the SUPERPET. In the next issue of The Transactor, I will cover the 6 809 ASSEMBLER/DEVELOPMENT package plus some technical aspect of the SUPERPET. The SUPERPET has brought an exciting concept to micro computers and to this end I will try and share with you as much as I can prior to its release.
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